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71.
Emma M. Smith Danelle Fuller Hina Mahmood 《Disability and rehabilitation. Assistive technology》2018,13(6):523-526
Purpose: To determine if older adult, novice wheelchair users who drive a power wheelchair with a JoyBar control complete maneuverability tasks in less time and with less error than those who drive a power wheelchair with a standard joystick control.Materials and methods: A parallel randomized controlled trial design conducted at a medical rehabilitation and research centre with ambulatory older adults aged 60 and above (n?=?27). The intervention was the JoyBar alternative wheelchair control. The primary outcome measure was total time to complete each of the two maneuverability tasks. The secondary outcome measure was total number of errors during each of the maneuverability tasks.Results: An independent, two sampled t-test was conducted and revealed that the JoyBar group took a greater amount of time to complete both maneuverability tasks than the control group (p?.05). No significant differences (p?.05) were found in rates of error on either task between the JoyBar and joystick groups.Conclusions: Maneuverability of a powered wheelchair by novice wheelchair users was not improved through the use of the JoyBar when compared to a standard wheelchair joystick, as measured by rates of error and time to complete maneuverability tasks.
- Implications for rehabilitation
Clients who are new to powered wheelchair use may perform maneuverability tasks faster, with equivalent accuracy, using a standard joystick versus the JoyBar.
Clients who use a JoyBar may require adjustments to the programming of their wheelchair to ensure optimal performance.
Additional training may be required to achieve proficiency in maneuverability tasks with a JoyBar versus a standard joystick.
72.
Aspects of control and substance use among middle‐aged and older adults with bipolar disorder
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Marissa N. Stalman BSN Sarah L. Canham PhD Atiya Mahmood PhD David King PhD Norm O'Rourke PhD RPsych 《International journal of mental health nursing》2018,27(2):833-840
High prevalence rates of alcohol and substance use disorders have been reported among persons with bipolar disorder (BD). In the present study, we explored the daily experiences of middle‐aged and older adults living with BD who reported regular substance use and the ways in which participants expressed ‘control’ in relation to their use of alcohol and other substances. Semistructured, in‐depth interviews were conducted with 12 participants (nine women and three men), aged 36–57 years of age (mean = 49 years). Thematic analyses identified emergent themes and patterns in participants’ life histories. The theme of ‘control’ emerged as central to participants’ reports, and was organized into four categories: (i) substance use to control BD symptoms; (ii) substance use provides a sense of being in control; (iii) methods of controlled substance use; and (iv) not having control: overreliance on substances. Implications of the present study include the need for nurses to openly discuss the use of alcohol and other drugs with persons with BD, provide health information and screening, and determine whether persons with BD feel they have control over their substance use. Several lines of research with persons who have BD and use substances are suggested. 相似文献
73.
Benjamin M. Larimer Nicholas Phelan Eric Wehrenberg-Klee Umar Mahmood 《Molecular imaging and biology》2018,20(2):300-308
Purpose
HER3 (ERBB3) is a receptor tyrosine kinase that is implicated in treatment resistance across multiple cancers, including those of the breast, lung, and prostate. Overexpression of HER3 following targeted therapy can occur rapidly and heterogeneously both within a single lesion and across sites of metastasis, making protein quantification by biopsy highly challenging. A global, non-invasive methodology such as positron emission tomography (PET) imaging can permit serial quantification of HER3, providing a useful approach to monitor HER3 expression across the entire tumor burden both prior to and following treatment. PET imaging of HER3 expression may permit a more personalized approach to targeted therapy by allowing for detection of HER3-mediated resistance, in addition to informing clinical trial patient selection for novel therapies targeting HER3.Procedures
Phage display selection targeting the HER3 extracellular domain was performed in order to develop a peptide with optimal blood clearance and highly accurate HER3 quantification.Results
The selection converged to a consensus peptide sequence that was subsequently found to bind HER3 with an affinity of 270 ± 151 nM. The peptide, termed HER3P1, was bound with high selectivity to HER3 over other similar receptor tyrosine kinases such as EGFR and HER2. Furthermore, HER3P1 was able to distinguish between high and low HER3-expressing cells in vitro. The peptide was radiolabeled with Ga-68 and demonstrated to specifically bind HER3 by in vivo PET imaging. Uptake of [68Ga]HER3P1 was highly specific for HER3-positive tumors, with tumor-to-background ratios ranging from 1.59–3.32, compared to those of HER3-negative tumors, ranging from 0.84–0.93. The uptake of [68Ga]HER3P1 also demonstrated high (P < 0.001) correlation with protein expression as quantified by Western blot and confirmed by biodistribution.Conclusions
HER3P1 accurately quantifies expression of HER3 by PET imaging and has potential utility as a clinical imaging agent.74.
Venkat Bhat Mahmood Tazari Kymberly D. Watt Mamatha Bhat 《Mayo Clinic proceedings. Mayo Clinic》2018,93(12):1794-1802
Objective
To identify key predictors and survival outcomes of new-onset diabetes after transplant (NODAT) in liver transplant (LT) recipients by using the Scientific Registry of Transplant Recipients.Patients and Methods
Data of all adult LT recipients between October 1, 1987, and March 31, 2016, were analyzed using various machine learning methods. These data were divided into training (70%) and validation (30%) data sets to robustly determine predictors of NODAT. The long-term survival of patients with NODAT relative to transplant recipients with preexisting diabetes and those without diabetes was assessed.Results
Increasing age (odds ratio [OR], 1.01; 95% CI, 1.00-1.02; P≤.001), male sex (OR, 1.09; 95% CI, 1.05-1.13; P=.03), and obesity (OR, 1.13; 95% CI, 1.08-1.18; P<.001) were significantly associated with NODAT. Sirolimus as a primary immunosuppressant carried a 33% higher risk of NODAT than did tacrolimus (OR, 1.33; 95% CI, 1.22-1.45; P<.001) at 1 year after LT. Patients with NODAT had significantly decreased 10-year survival than did those without diabetes (63.0% vs 74.9%; P<.001), similar to survival in patients with diabetes before LT (58.9%).Conclusion
Using a machine learning approach, we found that older, male, and obese recipients are at especially higher risk of NODAT. Donor features do not affect risk. In addition, sirolimus-based immunosuppression is associated with a significantly higher risk of NODAT than other immunosuppressants. Most importantly, NODAT adversely affects long-term survival after LT in a manner similar to preexisting diabetes, indicating the need for more aggressive care and closer follow-up. 相似文献75.
Identification of novel CYP1B1 gene mutations in patients with primary congenital and primary open‐angle glaucoma
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76.
Jila Yavarian Farshid Rezaei Azadeh Shadab Mahmood Soroush Mohammad Mehdi Gooya Talat Mokhtari Azad 《Emerging infectious diseases》2015,21(2):362-364
During January 2013–August 2014, a total of 1,800 patients in Iran who had respiratory illness were tested for Middle East respiratory syndrome coronavirus. A cluster of 5 cases occurred in Kerman Province during May–July 2014, but virus transmission routes for some infections were unclear. 相似文献
77.
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79.
Interactions between vascular endothelial cells and blood platelets have been investigated using a model microcirculation consisting of microcarrier beads colonized with human umbilical vein endothelial cells (HUVECs) and perfused with washed platelet suspensions. To simulate the effects of endothelial desquamation and exposure of subendothelium, fibrillar collagen in suspension was coinjected with the platelets. In this model, neither the passage of platelets alone nor collagen alone stimulated prostacyclin (PGI2) production by the HUVECs. Platelets activated by coinjection with collagen released thromboxane A2 (TXA2), and this was associated with the simultaneous production of PGI2 by the HUVECs. By means of double-isotope experiments with [3H]arachidonic acid (AA) incorporated into platelets and [14C]-AA into HUVECs, it was shown that all the PGI2 generated was derived from platelet AA and/or endoperoxides. This interpretation was strengthened by the finding that PGI2 production was not prevented by treatment of HUVECs with indomethacin followed by perfusion with collagen-stimulated platelets. AA metabolites in double-isotope label experiments were further characterized by reverse-phase chromatography, and it was shown that both cyclooxygenase and lipoxygenase products of the HUVECs were derived from platelet membrane lipid. Thrombin regularly produced transient PGI2 release, but showed rapid tachyphylaxis. Platelet-derived compounds including ADP, ATP, and platelet-activating factor (PAF) did not produce PGI2 release by HUVECs in this system. Thus, the transfer of AA and metabolites from collagen- stimulated platelets is likely to be the mechanism for PGI2 production in the context of minor degrees of endothelial desquamation. 相似文献
80.